1. Field of the Invention
The present invention concerns a method and an arrangement for positioning a patient in a medical diagnosis device or therapy device (medical device) of the type having a unit that interacts with the patient, a computer, and a patient bed that can be adjusted in at least one plane, and at least one image-recording device that acquires an image of the exterior of the patient and displays it on a screen, and an image processor that supervises or controls the positioning of the patient, wherein the computer “knows” the spatial correlation between the coordinate system of the treatment unit and the image-recording device.
2. Description of the Prior Art
A method and arrangement of the above general type are known from German published application 195 08 715. A medical diagnosis device with a method for positioning a patient in this diagnosis device is described in this application, wherein an image-recording device detects and localizes, by image processing, a marking applied to the patient before the imaging, such that a spatial correlation between the detected position of the patient and the coordinate system of the diagnosis device can be established, and the patient bed is subsequently automatically moved into a desired position. It is problematic that a marking first must be applied on the patient by the treating physician or appropriately trained medical personnel. The application of such markings to the patient can be undesirable for various reasons, so that this method and the corresponding device are not suitable in every situation.
Another similar method and a similar device are known from the German published application 101 09 219, corresponding to co-pending United States co-pending application Ser. No. 10/081,225 field Feb. 22, 2002 and published as Pub. No. 2002/0118280 (both publications occurring after the priority date of the present application). An imaging diagnosis system with a positioning device is described, wherein an image of the patient on the patient bed is acquired by at least one image-recording device and the image is displayed on a monitor. The operating personnel can manually select the desired examination region in the image on the screen with a region selection device, by the operator designating the desired examination region (for example, with a mouse or with a touch screen) with a drawn rectangle. On the basis of the indicated scan area, the positioning device subsequently guides the patient in the diagnosis system to the desired position and implements the examination in this region.
Such a procedure requires a very good training of the operating personnel, since it is expected that the operator can correctly convert the medical specifications into the correct scan area, which is then entered as an input. This method is also susceptible to error in the form of individual input error. Moreover, since the input is dependent on the individual operating person, different actual scan areas for examination of the same diagnostic region can be entered from different operating personnel.
Furthermore, it is commonly known that positioning of the patient by means of light or laser beam localizers is available as an alternative to the positioning devices and positioning methods that are based on a topogram (exterior image). In such techniques, the indication of the length of the scan area is shown by light markings, such that the operation makes the corresponding adjustment of the scan area directly on the patient.
In all of the cases cited above, a manual, time-consuming, and less-than-satisfactory interaction is required on the part of the operating personnel, which is regarded as disadvantageous, particularly in survey examinations. If topogram recordings are produced in addition to exact positionings, it results in an increased stress on the patient that should likewise be avoided.